Section 8(2)(a) in The Gujarat Value Added Tax Act, 2003
(a)if the amount of tax chargeable in relation to that sale exceeds the amount of tax actually accounted for by the seller, the amount of that excess shall be deemed to be tax charged by such seller in relation to a taxable sale attributable to the tax period in which the adjustment is to be made, and shall not be attributable to any prior tax period; or